Multi-omics analysis delineates the distinct functions of sub-cellular acetyl-CoA pools in Toxoplasma gondii

• Published in: BMC biology Vol. 18; no. 1; p. 67
• Main Authors: Kloehn, Joachim, Oppenheim, Rebecca D, Siddiqui, Ghizal, De Bock, Pieter-Jan, Kumar Dogga, Sunil, Coute, Yohann, Hakimi, Mohamed-Ali, Creek, Darren J, Soldati-Favre, Dominique
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 16-06-2020; BioMed Central; BMC
• Subjects: Acetyl Coenzyme A - genetics; Acetyl Coenzyme A - metabolism; Acetyl-CoA; Acetyl-CoA synthetase (ACS); Acetylation; Acetylome; Adaptation; Analysis; ATP citrate lyase; ATP citrate lyase (ACL); Biochemistry; Biochemistry, Molecular Biology; Branched-chain α-keto acid dehydrogenase-complex (BCKDH); Cell division; Chain branching; Chromatography; Cytosol; Defects; Dehydrogenase; Dehydrogenases; Elongation; Enzymes; Fatty acids; Gene expression; Gene regulation; Genomes; International economic relations; Life Sciences; Ligases; Metabolic pathways; Metabolism; Metabolites; Metabolome - genetics; Microbiology and Parasitology; Mitochondria; Morphology; Parasites; Parasitology; Pharmaceutical industry; Physiological aspects; Physiology; Pools; Post-translation; Post-translational modifications; Proteins; Proteome - genetics; Proteome - metabolism; Proteomes; Protozoan Proteins - genetics; Protozoan Proteins - metabolism; Pyruvate dehydrogenase (lipoamide); Pyruvic acid; Scientific equipment industry; Toxoplasma - enzymology; Toxoplasma gondii; Transcription; Transcriptome - genetics; Translation; Tricarboxylic acid cycle; United States; ATP citrate lyase (ACL); Toxoplasma gondii; Acetylome; Phosphoenolpyruvate carboxykinase (PEPCK); Acetyl-CoA; Acetyl-CoA synthetase (ACS); Metabolism; Formate/nitrite transporter (FNT); Multi-omics; Branched-chain α-keto acid dehydrogenase-complex (BCKDH)
• ISSN: 1741-7007; 1741-7007
• DOI: 10.1186/s12915-020-00791-7

Acetyl-CoA is a key molecule in all organisms, implicated in several metabolic pathways as well as in transcriptional regulation and post-translational modification. The human pathogen Toxoplasma gondii possesses at least four enzymes which generate acetyl-CoA in the nucleo-cytosol (acetyl-CoA synthetase (ACS); ATP citrate lyase (ACL)), mitochondrion (branched-chain α-keto acid dehydrogenase-complex (BCKDH)) and apicoplast (pyruvate dehydrogenase complex (PDH)). Given the diverse functions of acetyl-CoA, we know very little about the role of sub-cellular acetyl-CoA pools in parasite physiology.
To assess the importance and functions of sub-cellular acetyl-CoA-pools, we measured the acetylome, transcriptome, proteome and metabolome of parasites lacking ACL/ACS or BCKDH. We demonstrate that ACL/ACS constitute a synthetic lethal pair. Loss of both enzymes causes a halt in fatty acid elongation, hypo-acetylation of nucleo-cytosolic and secretory proteins and broad changes in gene expression. In contrast, loss of BCKDH results in an altered TCA cycle, hypo-acetylation of mitochondrial proteins and few specific changes in gene expression. We provide evidence that changes in the acetylome, transcriptome and proteome of cells lacking BCKDH enable the metabolic adaptations and thus the survival of these parasites.
Using multi-omics and molecular tools, we obtain a global and integrative picture of the role of distinct acetyl-CoA pools in T. gondii physiology. Cytosolic acetyl-CoA is essential and is required for the synthesis of parasite-specific fatty acids. In contrast, loss of mitochondrial acetyl-CoA can be compensated for through metabolic adaptations implemented at the transcriptional, translational and post-translational level.